JAKARTA, Sept 23 (Reuters) - Indonesian authorities are monitoring the financial market situation in China, finance minister Sri Mulyani Indrawati said on Thursday, and warned that property firm China Evergrande"s debt woes could affect the world"s economy. "We see a new risk to the financial system stability in China," she told a news conference. "They are going through a situation that is not easy and could have an extraordinary ripple effect not just for China"s domestic economy, but also the world"s. So we have to be careful."